1. Field of the Invention
The present invention relates to the field of medical devices and advising systems. More specifically, the present invention relates to allergen detection and air or asthma related advising systems.
2. Background Information
Asthma is a chronic disease that affects among other things, the lung functions of a patient. It is estimated that 6% to 9% of the population of the developed world are affected, and the number of diagnosed cases is growing at 5% per year, ten times the rate of population growth. The number of newly diagnosed cases of pediatric asthma has the health authorities of many countries consider asthma to be an epidemic. In United States, about 15 millions American are affected, making it the sixth ranked chronic disease of the country. About 5,500 people die from asthma related complication each year. The annual medical cost is estimated to be $6 billion. In addition, thousands of work and school days are lost.
Lung irritants such as particulates, plants and animal allergens, and certain types of man-made pollution are the usual triggers leading to asthma attacks. Typically, they are 50 microns or smaller. In the home setting, recent research has determined that allergens can accumulate to levels 2.times.-10.times. higher than outside levels. More importantly, "respirable" particulates less than 5 microns in size are of particular concern to health authorities. Current asthma treatment guidelines typically advise a patient to, in order of priority, (1) prevent an attack by avoiding asthma triggers, (2) check their lung function regularly and (3) take medication when necessary.
Although prevention is a high priority or even preferred aspect of the treatment plan for a patient, currently, very limited help is available to assist a patient to avoid asthma triggers, especially in the home setting. This is because allergenic particles that are 50 microns or smaller in size are too small to see without a microscope. Much of the air monitoring devices known in the art are catered for commercial (i.e. workplace) use, designed to monitor industrial pollutants. U.S. Pat. Nos. 5,001,463 and 5,646,597 issued to Hamburger disclosed two allergen detection devices for triggering an alarm when allergen level exceeding certain predetermined threshold is detected. A filter, collection and detection arrangement is employed in the '463 patent, whereas the '597 patent improves on the optical detection of the '463 patent. However, both devices suffer from at least the following disadvantages:
(a) neither devices are designed to detect respirable allergens that are smaller than 5 microns, which as mentioned above, have recently been identified by medical research as among the most relevant allergens to avoid; PA1 (b) both devices are only capable of generating an alarm based on the amount of allergens detected in the ambient air of the location of the monitoring device, which when located indoor, ignore the critical component of outdoor air quality (i.e. the air quality of the immediate outdoor area surrounding the indoor location); PA1 (c) the vertical sampling arrangement requires the use of extensive filtering and purging system; PA1 (d) the art ignores the role of humidity and temperature in the lung function; PA1 (e) maintaining, including cleaning, and calibrating these devices are difficult, requiring extensive disassembly and instrumentation; and PA1 (f) no provisions are provided for storing and communicating the collected data.
Thus, an improved approach to allergen monitoring and air/asthma advice generation is desired.
3. Terminology
Throughout the remaining specification, including the claims, usage of the term "allergen" is intended to include particulates, plants and animal allergens, man-made pollution, and the like, and usage of the term "air/asthma advice" is intended to cover air quality and/or asthma related information, suggestion, counsel, guidance, recommendation, admonition, direction, instruction, alert, warning, and the like.